Lightning-arrester.



G. GILES.

LIGHTNING ARRESTEH,

APPLICATION FILED JULY 10.1913.

1 1 1 1 3 Patented Sept. 22, 1914.

UNITED STATES PATENT oFFIcE,

GEORGES GILES, 0F FRIBOURG, SWITZERLAND.

LIGHTNING-ARRESTER.

To all whom it may concern:

Be it known that I, GEORGES GILES, engineer, a citizen of the United States, residing at F'ribourg, Canton of Fribourg, 1n the Confederation of Switzerland, have mvented certain new and useful Improvements in Lightning-Arresters, of wh ch the following is a specification. The present invention relates to an 1mproved safety device for the dissipatlon of excess voltage in electrical systems, and is an improvement upon the apparatus described in Patent No. 1,040,952 granted to me October 8, 1912.-

The device of my present lnvention comprises an adjustable spark gap in series with a high resistance andwith a series of electrodes between which spark gaps are pro' vided, and a movable conductor forming a common element for a plurality of condens'ers, the other elements of which are the said electrodes, one extreme electrode being electrically connected to the said reslstance while the other extreme electrode is electrically connected to the said conductor. In order to obtain adequate protection of an electric line by means of a device of this kind, it is" necessary for the apparatus to' permit of an easy dissipation or discharge of the excess voltages, limiting the value which practically can be given to the resistance in series with the spark ga s, in order that the device may have su cient capacity for the discharge of an excess volt-' age. The device may be compared to a valve in a water pipe, the opening of the valve, under excessive pressure being similar to the way of dischar e of an excessive voltage therethrough. n the other hand, durmg the dissipation of an excess voltage, the device must absorb a quantity of energy equal to that supplied by the central station or the generators feeding the line on which the device is placed. In order that this device may not be destroyed by the quantity of energy to be absorbed it must be operated only during short intervals. In electric lines in which it is usual to employ protective devices of this nature, variations of tension may occur and be maintained during an ap preciable time, for which variations the device must be inoperative. Ordinarily these variations of tension do not exceed twice the normal voltage of the line. Therefore a sufficient protection will be obtained by means of an apparatus regulated to operate Specification of Letters Patent.

Application filed July 10, 1913'.

Patented Sept. 22, 1914. Serial No. 778,263.

on excess voltages, which exceed twice the selves, the extinction of the sparks in the spark gaps after a determined working-time 'of-the apparatus is obtained, according to the present invention, by means of the movability of the common conductor relatively to the electrodes. connection between the conductor and the small condensers after the apparatus has worked a given length of time.

The accompanying drawing is a longitudinal section and elevation of the apparatus.

a, a are the electrodes between which the adjustable spark gap is provided. These electrodes are placed in an envelop b, which is-made for instance of glass and is arranged on the upper portion of a tube 0 of insulating material upon which the wire 01 which forms the resistance in series with the electrodes at and a is wound.

f F, f designate the electrodes of the non adjustable spark gaps the first of which is connected to the resistance formed by the wire (Z. These electrodes are insulated from each other and from their common support consisting of the tube 9 on which they are placed, by means of insulating rings h. Within the tube 9 of insulating material, the conducting rod 6 is placed. To this rod the last electrode 7 is directly electrically connected, this rod forming a common armature of small condensers the other armatures of which are formed by the electrodes themselves and by means of which the electrodes are connected to the common conductor which is formed by the rod 2'. The latter is movable within the tube 9 which projects. through the tube 0 and carries at its upper end the electrode a'. The rod 6 fits frictionally within the tube 9 in such a manner that in use it will not fall therefrom, as is indicated in the drawing, or, as will be understood, the rod 2' may be suitably supported the end thereof which extends beyond the This movability breaks the normal and the apparatus is not in use. In the case of an excessive voltage .a spark is caused to pass between the electrodes m -and a and is followed in the well known manner by the formation of sparks between the electrodes #inerder' to discharge the excess voltage to earth. The spark between the electrodes a and a causes the heating of the air inclosed in the envelop b, which air passing into the upper portion of the tube causes the displacement of the rod iwit regard to the electrodes 7. These electrodes then ceasing to be elements of condensers, which they form with the rod c, as the other and common element, a voltage which is much higher than the starting voltage is necessary for making'or maintaining the sparks in the spark gaps, and this assures the extinction of the sparks after a short period of operating. Instead of placing the electrodes of the non adjustable spark gaps on a tube within which the rodformingthe common conductor is slidably arranged, these electrodes may for instance be ar ranged Within a conducting tube serving as conductor and common armature to the small condensers which connect the elec- I trodes to the conductor.

I claim as my invention: 1. A device of the character described, comprising adjustable electrodes providing a variable spark gap, a series of fixed spaced 7 ring electrodes providing a plurality of in termediate constant spark gaps, and a conductor movable within said fixed electrodes, the extreme end one of which is electrically connected'to the said conductor while all of. the others are insulated therefrom.

2. A device of the character described,

.comprisinga pair of adjustable electrodes providing a variable spark gap, -a series of fixed spaced ring electrodes providing a plurality of intermediate constant spark gaps, a resistance connecting one. member of the saidpair of electrodes and the end a ring electrode next adjacent the same, and

a conductor movable concentrically within the said fixed electrodes, the opposite extreme end one of which is'electrically connected to the conductor while all the others I are insulated therefrom. I

3. A device of the character described,

comprising a housing, a .pair of electrodes, 1

' one of which is fixed and the other movable in the said housing, providing a variable spark gap therein, a casing connected to the said housing, a series of fixed spaced ring electrodes providin a plurality of interme diate constant spar vgaps, a resistance surrounding the said casing and connecting the electrode fixed in the housing and the nearest adjacent of the said ring electrodes, a tube extending through the said series of inxed ring electrodes and through the said I casing, and a conductor within the said tube and electrically connected to the fixed ring electrode at the opposite endof the series' thereof, while all of the other ring electrodes are insulated from the said conductor and from each other, there being a passage through the electrode fixed in the housing so as to provide communication between the interior thereof and the said tube.

- In testimony whereof I have aflixed my signature in presence of two witnesses.

. GEORGES GILES Witnesses:

G. IMER, I LoUIs H. MUNIER. 

